Power allocation across multiple carriers using shared and dedicated radio frequency spectrum

Abstract

Methods, systems, and devices for wireless communication are described that provide for power allocation across different carriers using shared and dedicated radio frequency spectrum for a power-limited UE. In cases where a power-limited UE is to transmit control information, power allocation across different carriers may be determined based on one or more of a number of parameters, such as a type of control channel for transmission of control information, an outcome of an LBT procedure for a carrier using shared radio frequency spectrum, a timing of the LBT procedure, one or more other concurrent transmissions, or any combination thereof.

What is claimed is: 
     
       1. A method for wireless communication, comprising:
 identifying a first carrier and a second carrier that are scheduled for a transmission in a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 performing a listen before talk (LBT) procedure to determine availability of the second carrier for transmissions during the TTI; 
 prioritizing at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier; and 
 allocating the total transmission power for the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of control information during the TTI, an outcome of the LBT procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier. 
 
     
     
       2. The method of  claim 1 , wherein the second carrier is scheduled for transmissions in each of the plurality of subframes, and wherein the allocating further comprises:
 determining the first portion of the total transmission power to be allocated to the second carrier irrespective of the scheduled transmission of the first carrier; 
 reducing the first portion of the total transmission power based at least in part on a parameter associated with a transmission using the second carrier; 
 allocating the reduced first portion of the total transmission power to the second carrier for each of the plurality of subframes; and 
 allocating a difference between the total transmission power and the reduced first portion of the total transmission power to the first carrier. 
 
     
     
       3. The method of  claim 2 , wherein the parameter associated with the transmission using the second carrier comprises a modulation and coding scheme (MCS), a redundancy version identification (RV ID), a power loss (PL) measurement, or any combination thereof. 
     
     
       4. The method of  claim 1 , wherein the allocating further comprises:
 determining whether the second carrier is scheduled for transmission in a third subframe of the plurality of subframes after the second subframe; 
 dropping the first carrier in the second subframe; and 
 allocating the total transmission power to the second carrier. 
 
     
     
       5. The method of  claim 1 , wherein the allocating further comprises:
 determining that control information and shared channel information is scheduled to be transmitted on the first carrier during the second subframe; 
 diverting a portion of the total transmission power to the first carrier; 
 transmitting the control information using the first carrier; and 
 dropping the shared channel information scheduled to be transmitted on the first carrier. 
 
     
     
       6. The method of  claim 1 , wherein the allocating further comprises:
 determining that control information and shared channel information is scheduled to be transmitted on the first carrier during the second subframe and that only the shared channel information is scheduled to be transmitted on the second carrier during the second subframe; 
 diverting a first portion of the total transmission power to the first carrier; 
 transmitting the control information and the shared channel information using the first carrier; and 
 transmitting the shared channel information scheduled to be transmitted on the second carrier. 
 
     
     
       7. The method of  claim 6 , wherein a ratio of the total transmission power to divert is based at least in part on whether channel state information (CSI) is to be transmitted using the second carrier. 
     
     
       8. The method of  claim 1 , wherein each of the first carrier and the second carrier are scheduled for transmissions in a first subframe immediately following completion of the LBT procedure, and wherein the allocating further comprises:
 pre-allocating, prior to performing the LBT procedure, the first portion of the total transmission power to the first carrier and the difference between the total transmission power and the first portion of the total transmission power to the second carrier. 
 
     
     
       9. The method of  claim 8 , wherein a ratio between the first portion and the total transmission power is determined based at least in part on whether control channel information scheduled on one or more of the first carrier or the second carrier, or whether channel state information (CSI) is to be transmitted using a physical uplink shared channel (PUSCH). 
     
     
       10. The method of  claim 8 , further comprising:
 transmitting a first portion of a first subframe following the LBT procedure using the pre-allocated transmission powers; 
 reallocating the total transmission power for the TTI across the first carrier and the second carrier based at least in part on the outcome of the LBT procedure; and 
 transmitting a remaining portion of the first subframe using the reallocated transmission powers. 
 
     
     
       11. The method of  claim 1 , wherein each of the first carrier and the second carrier are scheduled for transmissions in the first subframe and the LBT procedure is completed during the first subframe, and wherein the allocating further comprises:
 pre-allocating, prior to performing the LBT procedure, the first portion of the total transmission power to the first carrier and the difference between the total transmission power and the first portion of the total transmission power to the second carrier; and 
 transmitting on the first carrier during an entirety of the first subframe using the first portion of the total transmission power regardless of the outcome of the LBT procedure. 
 
     
     
       12. The method of  claim 1 , wherein allocating the total transmission power for the TTI across the first carrier and the second carrier is further based on whether the first carrier is associated with a primary cell or a primary secondary cell. 
     
     
       13. A method for wireless communication, comprising:
 identifying a user equipment (UE) capable of transmitting using both a first carrier and a second carrier, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band; 
 allocating wireless resources of the first carrier and the second carrier to the UE for uplink transmissions during a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 configuring the UE to prioritize at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier; 
 configuring the UE to allocate the total transmission power for the uplink transmissions during the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of the control information during the TTI, an outcome of a listen before talk (LBT) procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier; and 
 receiving the uplink transmissions from the UE on at least one of first carrier or the second carrier. 
 
     
     
       14. An apparatus for wireless communication, comprising:
 means for identifying a first carrier and a second carrier that are scheduled for a transmission in a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 means for performing a listen before talk (LBT) procedure to determine availability of the second carrier for transmissions during the TTI; 
 means for prioritizing at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier; and 
 means for allocating the total transmission power for the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of control information during the TTI, an outcome of the LBT procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier. 
 
     
     
       15. The apparatus of  claim 14 , wherein
 the means for allocating the total transmission power for the TTI across the first carrier and the second carrier comprises:
 means for determining whether the second carrier is scheduled for transmission in a third subframe of the plurality of subframes after the second subframe; 
 means for dropping the first carrier in the second subframe; and 
 means for allocating the total transmission power to the second carrier. 
 
 
     
     
       16. The apparatus of  claim 14 , wherein
 each of the first carrier and the second carrier are scheduled for transmissions in a first subframe immediately following completion of the LBT procedure, and 
 wherein the means for allocating the total transmission power for the TTI across the first carrier and the second carrier comprises means for pre-allocating, prior to performing the LBT procedure, the first portion of the total transmission power to the first carrier and the difference between the total transmission power and the first portion of the total transmission power to the second carrier. 
 
     
     
       17. The apparatus of  claim 14 , wherein allocating the total transmission power for the TTI across the first carrier and the second carrier is further based on whether the first carrier is associated with a primary cell or a primary secondary cell. 
     
     
       18. An apparatus for wireless communication, comprising:
 means for identifying a user equipment (UE) capable of transmitting using both a first carrier and a second carrier, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band; 
 means for allocating wireless resources of the first carrier and the second carrier to the UE for uplink transmissions during a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 means for configuring the UE to prioritize at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier: 
 means for configuring the UE to allocate the total transmission power for the uplink transmissions during the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of the control information during the TTI, an outcome of a listen before talk (LBT) procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier; 
 means for and 
 means for receiving the uplink transmissions from the UE on at least one of first carrier or the second carrier. 
 
     
     
       19. An apparatus for wireless communication, in a system comprising:
 a processor; 
 memory in electronic communication with the processor; and 
 instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:
 identify a first carrier and a second carrier that are scheduled for a transmission in a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 perform a listen before talk (LBT) procedure to determine availability of the second carrier for transmissions during the TTI; 
 prioritize at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier; and 
 allocate the total transmission power for the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of control information during the TTI, an outcome of the LBT procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier. 
 
 
     
     
       20. The apparatus of  claim 19 , wherein
 the instructions executable by the processor to allocate a total transmission power for the TTI across the first carrier and the second carrier comprise instructions executable by the processor to:
 determine the first portion of the total transmission power to be allocated to the second carrier irrespective of the scheduled transmission of the first carrier; 
 reduce the first portion of the total transmission power based at least in part on a parameter associated with a transmission using the second carrier; 
 allocate the reduced first portion of the total transmission power to the second carrier for each of the plurality of subframes; and 
 allocate a difference between the total transmission power and the reduced first portion of the total transmission power to the first carrier. 
 
 
     
     
       21. The apparatus of  claim 20 , wherein the parameter associated with the transmission using the second carrier comprises a modulation and coding scheme (MCS), a redundancy version identification (RV ID), a power loss (PL) measurement, or any combination thereof. 
     
     
       22. The apparatus of  claim 19 , wherein
 the instructions executable by the processor to allocate the total transmission power for the TTI across the first carrier and the second carrier comprise instructions executable by the processor to:
 determine whether the second carrier is scheduled for transmission in a third subframe of the plurality of subframes after the second subframe; 
 drop the first carrier in the second subframe; and 
 allocate the total transmission power to the second carrier. 
 
 
     
     
       23. The apparatus of  claim 19 ,
 wherein the instructions executable by the processor to allocate a total transmission power for the TTI across the first carrier and the second carrier comprise instructions executable by the processor to:
 determine that control information and shared channel information is scheduled to be transmitted on the first carrier during the second subframe; 
 divert a portion of the total transmission power to the first carrier; 
 transmit the control information using the first carrier; and 
 drop the shared channel information scheduled to be transmitted on the first carrier. 
 
 
     
     
       24. The apparatus of  claim 19 ,
 wherein the instructions executable by the processor to allocate the total transmission power for the TTI across the first carrier and the second carrier comprise instructions executable by the processor to:
 determine that control information and shared channel information is scheduled to be transmitted on the first carrier during the second subframe and that only the shared channel information is scheduled to be transmitted on the second carrier during the second subframe; 
 divert a first portion of the total transmission power to the first carrier; 
 transmit the control information and the shared channel information using the first carrier; and 
 transmit the shared channel information scheduled to be transmitted on the second carrier. 
 
 
     
     
       25. The apparatus of  claim 24 , wherein a ratio of the total transmission power to divert is based at least in part on whether channel state information (CSI) is to be transmitted using the second carrier. 
     
     
       26. The apparatus of  claim 19 , wherein
 each of the first carrier and the second carrier are scheduled for transmission in a first subframe immediately following completion of the LBT procedure, and 
 wherein the instructions further comprise instructions executable by the processor to pre-allocate, prior to performing the LBT procedure, the first portion of the total transmission power to the first carrier and the difference between the total transmission power and the first portion of the total transmission power to the second carrier. 
 
     
     
       27. The apparatus of  claim 26 , wherein a ratio between the first portion and the total transmission power is determined based at least in part on whether control channel information is scheduled for transmission on one or more of the first carrier or the second carrier, or whether channel state information (CSI) is to be transmitted using a physical uplink shared channel (PUSCH). 
     
     
       28. The apparatus of  claim 26 , wherein the instructions comprise instructions executable by the processor to:
 transmit a first portion of a first subframe following the LBT procedure using the pre-allocated transmission powers; 
 reallocate the total transmission power for the TTI across the first carrier and the second carrier based at least in part on the outcome of the LBT procedure; and 
 transmit a remaining portion of the first subframe using the reallocated transmission powers. 
 
     
     
       29. The apparatus of  claim 19 , wherein
 each of the first carrier and the second carrier are scheduled for transmissions in the first subframe and the LBT procedure is completed during the first subframe, and 
 wherein the instructions are operable, when executed by the processor, to cause the apparatus to:
 pre-allocate, prior to performing the LBT procedure, the first portion of the total transmission power to the first carrier and the difference between the total transmission power and the first portion of the total transmission power to the second carrier; and 
 transmitting on the first carrier during an entirety of the first subframe using the first portion of the total transmission power regardless of the outcome of the LBT procedure. 
 
 
     
     
       30. The apparatus of  claim 19 , wherein allocating the total transmission power for the TTI across the first carrier and the second carrier is further based on whether the first carrier is associated with a primary cell or a primary secondary cell. 
     
     
       31. An apparatus for wireless communication, in a system comprising:
 a processor; 
 memory in electronic communication with the processor; and 
 instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:
 identify a user equipment (UE) capable of transmitting using both a first carrier and a second carrier, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band; 
 allocate wireless resources of the first carrier and the second carrier to the UE for uplink transmissions during a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 configure the UE to prioritize at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier; 
 configure the UE to allocate the total transmission power for the uplink transmissions during the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of the control information during the TTI, an outcome of a listen before talk (LBT) procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier; and 
 receive the uplink transmissions from the UE on at least one of first carrier or the second carrier. 
 
 
     
     
       32. A non-transitory computer readable medium storing code for wireless communication, the code comprising instructions executable by a processor to:
 identify a first carrier and a second carrier that are scheduled for a transmission in a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 perform a listen before talk (LBT) procedure to determine availability of the second carrier for transmissions during the TTI; 
 prioritize at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier; and 
 allocate the total transmission power for the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of control information during the TTI, an outcome of the LBT procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier. 
 
     
     
       33. The non-transitory computer readable medium of  claim 32 , wherein
 the code further comprises instructions executable by the processor to:
 determine whether the second carrier is scheduled for transmission in a third subframe of the plurality of subframes after the second subframe; 
 drop the first carrier in the second subframe; and 
 allocate the total transmission power to the second carrier. 
 
 
     
     
       34. The non-transitory computer readable medium of  claim 32 , wherein each of the first carrier and the second carrier are scheduled for transmissions in a first subframe immediately following completion of the LBT procedure, and wherein the code further comprises instructions executable by the processor to;
 pre-allocate, prior to performing the LBT procedure, the first portion of the total transmission power to the first carrier and the difference between the total transmission power and the first portion of the total transmission power to the second carrier. 
 
     
     
       35. The non-transitory computer readable medium of  claim 32 , wherein allocating the total transmission power for the TTI across the first carrier and the second carrier is further based on whether the first carrier is associated with a primary cell or a primary secondary cell. 
     
     
       36. A non-transitory computer readable medium storing code for wireless communication, the code comprising instructions executable by the processor to:
 identify a user equipment (UE) capable of transmitting using both a first carrier and a second carrier, the first carrier using a dedicated radio frequency spectrum band and the second carrier using a shared radio frequency spectrum band; 
 allocate wireless resources of the first carrier and the second carrier to the UE for uplink transmissions during a transmission time interval (TTI), wherein the TTI includes a plurality of subframes, and the second carrier is scheduled for transmissions in a first subframe and a second subframe that is after the first subframe, and the first carrier is scheduled for transmission in the second subframe; 
 configure the UE to prioritize at least one of the first carrier or the second carrier for power allocation based at least in part on a payload of control information, wherein the second carrier is prioritized to provide a first portion of a total transmission power to the second carrier irrespective of the scheduled transmission on the first carrier; 
 configure the UE to allocate the total transmission power for the uplink transmissions during the TTI across the first carrier and the second carrier based at least in part on the prioritizing and a type of control channel for transmission of the payload of the control information during the TTI, an outcome of a listen before talk (LBT) procedure, a timing of the LBT procedure relative to the TTI, one or more other transmissions to be transmitted during the TTI, or any combination thereof, wherein a difference between the total transmission power and the first portion of the total transmission power is allocated to the first carrier; and 
 receive the uplink transmissions from the UE on at least one of first carrier or the second carrier.